Page 4. Araneomorphs

Most New Zealand spiders are araneomorphs. Their fangs
move sideways (imagine your thumb and forefinger coming
together) rather than up and down like the mygalomorphs. With
this type of fang, araneomorphs do not need to have their
prey on a solid surface to strike, and can exploit a far
wider range of habitats than the mygalomorphs.

Spiders do not fly, but a lot of their food comes from
insects that can. Araneomorphs can directly catch flying
insects, and also use webs as aerial filters.

Orb-web spider

The common orb-web spider Eriophora pustulosa is
seen in gardens throughout New Zealand. Often its lines are
weighed down with drops of morning dew, making the web look
like a diamond necklace.

At night the spider either remakes or repairs the web, and
then waits for insects to fly into it once again. The
spiralling lines have tiny glue droplets which stick to an
insect that touches the web. Once the prey has been caught,
the spider wraps it in a shroud of silk so it cannot escape.
The ‘spokes’ of the web do not have glue, and are used as
attachment points for the spiralling threads.

Spinning a tale

In 1981 the novelist Patricia Grace published the
children’s book Te kuia me te pungawerewere or
The old woman and the spider. The spider is
probably the common grey house spider, Badumna
longinqua. The story tells of a spinning contest
between the two.

Grey house spider

The grey house spider Badumna longinqua is
probably the most common spider in New Zealand, and lives in
most homes and gardens. It arrived from Australia in the 19th
century.

Badumna has a comb of special hairs on its back
legs, to comb out the threads from its spinnerets. It builds
a cobweb with a narrow tube and traps prey with a fine ‘wool’
of threads between the structural threads. Tangled prey
vibrate the lines, alerting the spider.

Huntsman as stuntman

The Avondale spider (Delena cancerides) is a
huntsman spider from Australia, but in New Zealand it seems
to occur only in the Auckland suburb of Avondale. This is
one of New Zealand’s largest spiders, up to 20 centimetres
across. It was used in the 1990 film Arachnophobia
instead of a tarantula because it can run across walls,
while tarantulas tend to fall off.

Hunting spiders

Hunting spiders rely on stealth rather than webs. Two
common species are crab spiders and jumping spiders.

Crab spider

Crab spiders (Thomisidae family) are common on garden
plants, but are well camouflaged. They wait with outstretched
arms for insects to land on the plant, then grab them. Crab
spiders usually inject venom into the head of their victim
and suck out its insides. They leave the body intact.

Jumping spiders

Jumping spiders (Salticidae family) have eyesight to rival
a primate, and a mammal-like cunning. They will stalk a fly
on the edge of a table, then walk hidden towards it, checking
its position before pouncing. If the spider has to approach
directly, it will crouch down and move very slowly until
close enough to pounce – like a cat stalking a bird. When you
look at a jumping spider closely, it will often raise its
head and look back.

Hey, good-looking

Many jumping spiders look like tiny primates. Some have
moustache-like tufts, punk-style haircuts and
jewel-coloured scales decorating their faces and bodies, to
attract mates and scare off rivals. Males attract a mate by
waving their legs and posturing.

Water spiders

The common water spider Dolomedes aquaticus has
muted colouring that blends with river stones. It is not
normally seen during the day, but sits and waits for prey
after dark, and can survive under water for short
periods.